Answer:
The endocrine system secretes hormones into blood and other body fluids Hormones provide feedback to the brain to affect neural processing. Reproductive hormones affect the development of the nervous system.
Explanation:
C. Solar energy's whole purpose it to reduce pollution in the air that fossil feuls do not. The answer cannot be A. B. or D. because 1. it is expensive 2. it can only be used during the daytime. It is a SOLAR panel. and 3. like is said earlier it is not free.
By process of elimination you can find the right answer. We know for a fact that carbon is found in all living organisms. That is why we talk about carbon based life forms. So the first statement cannot be true. You can figure out how many Valence electrons an element has by looking at the group number. The group number of carbon is 4 so the 2nd statement cannot be true. We know that carbon does bond with other elements because it is not a noble gas and therefore must be able to form compounds.
This means the answer must be they can form up to four covalent bonds